OBJECTIVETo investigate the effect of 2-deoxy-D-glucose (2-DG) in enhancing the sensitivity of oral cancer cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis.

METHODSThe oral cancer cell line KB was incubated in the presence of different concentrations (0, 0.625, 1.25, 2.5, 5, and 10 mmol/L) of 2-DG with or without TRAIL (200 ng/ml). The cell viability was measured using MTT assay and cell apoptosis was detected using flow cytometry with propidium iodide (PI) staining. KB cells treated with 5 mmol/L 2-DG with or without TRAIL for 0, 6, 16, or 24 h were examined with Western blotting for protein expressions of death receptor 5 (DR5) and caspase-3.

RESULTSTreatment of the cells with 5 mmol/L 2-DG for 24, 48 and 72 h resulted in a cell viability of 25.25%, 69.06%, and 59.19%, respectively. Combined treatment with 5 mmol/L 2-DG with TRAIL for 24 significantly enhanced the cell apoptotic rate (72.5%) as compared to the rate induced by TRAIL alone (45.3%) and by 2-DG (15.9%) alone. 2-DG treatment markedly up-regulated DR5 and caspase-3 expression and enhanced the inhibitory effect of TRAIL on cell colony formation.

CONCLUSION2-DG sensitizes oral cancer cells to TRAIL- induced apoptosis by up-regulating DR5 and caspase-3 expressions.